path: root/scripts/sorttable.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * sorttable.c: Sort the kernel's table
 *
 * Added ORC unwind tables sort support and other updates:
 * Copyright (C) 1999-2019 Alibaba Group Holding Limited. by:
 * Shile Zhang <shile.zhang@linux.alibaba.com>
 *
 * Copyright 2011 - 2012 Cavium, Inc.
 *
 * Based on code taken from recortmcount.c which is:
 *
 * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>.  All rights reserved.
 *
 * Restructured to fit Linux format, as well as other updates:
 * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
 */

/*
 * Strategy: alter the vmlinux file in-place.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <getopt.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <pthread.h>

#include "elf-parse.h"

#ifndef EM_ARCOMPACT
#define EM_ARCOMPACT	93
#endif

#ifndef EM_XTENSA
#define EM_XTENSA	94
#endif

#ifndef EM_AARCH64
#define EM_AARCH64	183
#endif

#ifndef EM_MICROBLAZE
#define EM_MICROBLAZE	189
#endif

#ifndef EM_ARCV2
#define EM_ARCV2	195
#endif

#ifndef EM_RISCV
#define EM_RISCV	243
#endif

#ifndef EM_LOONGARCH
#define EM_LOONGARCH	258
#endif

typedef void (*table_sort_t)(char *, int);

/*
 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
 * the way to -256..-1, to avoid conflicting with real section
 * indices.
 */
#define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))

static inline int is_shndx_special(unsigned int i)
{
	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
}

/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
static inline unsigned int get_secindex(unsigned int shndx,
					unsigned int sym_offs,
					const Elf32_Word *symtab_shndx_start)
{
	if (is_shndx_special(shndx))
		return SPECIAL(shndx);
	if (shndx != SHN_XINDEX)
		return shndx;
	return elf_parser.r(&symtab_shndx_start[sym_offs]);
}

static int compare_extable_32(const void *a, const void *b)
{
	Elf32_Addr av = elf_parser.r(a);
	Elf32_Addr bv = elf_parser.r(b);

	if (av < bv)
		return -1;
	return av > bv;
}

static int compare_extable_64(const void *a, const void *b)
{
	Elf64_Addr av = elf_parser.r8(a);
	Elf64_Addr bv = elf_parser.r8(b);

	if (av < bv)
		return -1;
	return av > bv;
}

static int (*compare_extable)(const void *a, const void *b);

static inline void *get_index(void *start, int entsize, int index)
{
	return start + (entsize * index);
}

static int extable_ent_size;
static int long_size;

#define ERRSTR_MAXSZ	256

#ifdef UNWINDER_ORC_ENABLED
/* ORC unwinder only support X86_64 */
#include <asm/orc_types.h>

static char g_err[ERRSTR_MAXSZ];
static int *g_orc_ip_table;
static struct orc_entry *g_orc_table;

static pthread_t orc_sort_thread;

static inline unsigned long orc_ip(const int *ip)
{
	return (unsigned long)ip + *ip;
}

static int orc_sort_cmp(const void *_a, const void *_b)
{
	struct orc_entry *orc_a, *orc_b;
	const int *a = g_orc_ip_table + *(int *)_a;
	const int *b = g_orc_ip_table + *(int *)_b;
	unsigned long a_val = orc_ip(a);
	unsigned long b_val = orc_ip(b);

	if (a_val > b_val)
		return 1;
	if (a_val < b_val)
		return -1;

	/*
	 * The "weak" section terminator entries need to always be on the left
	 * to ensure the lookup code skips them in favor of real entries.
	 * These terminator entries exist to handle any gaps created by
	 * whitelisted .o files which didn't get objtool generation.
	 */
	orc_a = g_orc_table + (a - g_orc_ip_table);
	orc_b = g_orc_table + (b - g_orc_ip_table);
	if (orc_a->type == ORC_TYPE_UNDEFINED && orc_b->type == ORC_TYPE_UNDEFINED)
		return 0;
	return orc_a->type == ORC_TYPE_UNDEFINED ? -1 : 1;
}

static void *sort_orctable(void *arg)
{
	int i;
	int *idxs = NULL;
	int *tmp_orc_ip_table = NULL;
	struct orc_entry *tmp_orc_table = NULL;
	unsigned int *orc_ip_size = (unsi